Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

[NJCoastFlyFish]

I'm looking at two engines, a 60hp 3cyl and a 90hp 4cyl both from the late 80's.<br /><br />My question is will there be a significant difference in the fuel consumption of these two engines? Enough to make a difference for every trip that you need a few extra gallons for the v4?<br /><br />The problem is I would like the 60 3 cyl better because I would think it is more reliable and better of gas and that is what i'm looking for, but the guy selling the 60 is asking 300 more than the guy selling the 90 and the 90 is a REAL clean freshwater engine, so i'm stuck! <br /><br />What do you think of these choices?<br /><br />Oh yeah, and both are OMC

 

[moderator1]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

The 60 has better fuel economy, but the 90 V4 will have better reliability if well taken care of. The V4 will Idle much smoother if you do alot of trolling or just slow cruising around.<br />Expect 6-7GPH on the 60, and the 90 comes in around 9-11 GPH at WOT, depending how they are both set up prop-wise of course.

 

[LubeDude]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

You dont say what boat these will go on. If its a relativly light boat, you will see a better fuel economy figure with the 60. but if its a heavy long boat, you will have to push the 60 harder to achive the same speed, so there may be better economy with the 90 due to not having to run it at near WOT to achive the same speed. I think I said that right.

 

[Chinewalker]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

Here's a for-instance for you. At one time I was renting a cottage with a buddy. The cottage was on an island so we had to commute to our jobs by boat every day. We docked at the same location on the mainland, so we traveled about the same distance in our boats. I had a 16-foot openbow runabout with a 75hp Johnson 3-banger (very similar to the 60 in question) and he had an 88SPL V4 on a 17-foot Whaler Montauk. Neither of us really ran the boats hard, preferring to run at a decent cruising speed. Anyway, as a test, one week we both started the week with two fresh 6-gallon cans of fuel. By Friday morning he was switching over to his third tank on the same trip that I switched over to my second. Only a 15hp difference, but he was using almost twice as much fuel. Not real scientific, and not exactly apples to apples, but fairly significant in any case....<br />- Scott

 

[JB]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

Like Scott, my experience was with similar engines and with similar results.<br /><br />I had a 1960s 100hp V4 on my BW 16' and switched, mid season, to a 1980 70HP triple. Gas usage for very similar trips and similar useage was about half.<br /><br />The V4 90 you are looking at is probably a looper, which would be more efficient that my old crossflow, but the 60 would probably be more efficient than my 70. I still think the 60 would use a lot less fuel that the 90.

 

[NJCoastFlyFish]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

Wow, that is a significant difference in fuel consumption between the two. This engine would be going on an 66 whaler 16ft7in, relativelt bare boat, just have a console and swingback seat in it right now, so it is fairly light. Looks like the 3cyl is for me.<br /><br />On a side note, I would have though the 3cyl would be more reliable than the v4, smaller and less things that can go wrong, does everyone else agree a v4 90horse is more reliable than the 3cyl models?

 

[Chinewalker]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

I have no reason to say that the 3-cylinders are any less reliable than the V4s. I still own the 75 I had back when my buddy and I did that comparison is still going strong and has tons of hours on it - probably over 1500 and closing in on 2000 on a rebuild done in 1995. The only thing I ever had to replace on it was a powerpack about 6 seasons ago. I do the routine stuff - new impeller every three seasons, change the lower oil once a season and check it a couple other times just to keep an eye on it. I decarb it once a year and I run Bomby oil in it 75% of the time. Still punched the compression gauge into the 140s in all three holes last summer...<br /> Like anything, take care of it and it'll take care of you...<br />- Scott

 

[LubeDude]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

I think if you are not a speed deamon, the 60 might be your best choice here. That 90 would really kick bu*t on that boat though, and might add some retail value too.

 

[Texasmark]

Re: Fuel Consumption: Late 80's 60hp 3cyl vs 90hp 4cyl

Heads up call here. The 3 cylinder was a looper and the 4 cyl was crossflow. Day and night in fuel consumption considering the load was appropriate for the engine.<br /><br />Have had both. Very obvious fuel difference. Give the 4 ran smoother.<br /><br />How long will it take you to burn up the $300 in fuel? How important is fuel economy? What is the estimated "what needs fixing" between the engines? Answer those questions and you have answered your question.<br /><br />Did it ever occur to you why most all 2 cycles are loopers today; or the lineup includes a looper side by side with a crossflow?<br /><br />HTH<br /><br />Mark